20956165431 has 4 divisors (see below), whose sum is σ = 27941553912. Its totient is φ = 13970776952.

The previous prime is 20956165429. The next prime is 20956165453. The reversal of 20956165431 is 13456165902.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20956165431 - 2¹ = 20956165429 is a prime.

It is a super-2 number, since 2×20956165431² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20956165481) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3492694236 + ... + 3492694241.

It is an arithmetic number, because the mean of its divisors is an integer number (6985388478).

Almost surely, 2^20956165431 is an apocalyptic number.

20956165431 is a deficient number, since it is larger than the sum of its proper divisors (6985388481).

20956165431 is an equidigital number, since it uses as much as digits as its factorization.

20956165431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6985388480.

The product of its (nonzero) digits is 194400, while the sum is 42.

The spelling of 20956165431 in words is "twenty billion, nine hundred fifty-six million, one hundred sixty-five thousand, four hundred thirty-one".